gve: Remove dependency on 4k page size.

Prior to this change, gve crashes when attempting to run in kernels with
page sizes other than 4k. This change removes unnecessary references to
PAGE_SIZE and replaces them with more meaningful constants.

Signed-off-by: Jordan Kimbrough <jrkim@google.com>
Signed-off-by: John Fraker <jfraker@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20231128002648.320892-6-jfraker@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/google/gve/gve.h
index abc0c708b47ac73dfe59b0e3b7f0ac89f6325c49..b80349154604b11510637deebf908bbe3b73ac5e 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve.h
+++ b/drivers/net/ethernet/google/gve/gve.h
@@ -49,7 +49,9 @@
 /* PTYPEs are always 10 bits. */
 #define GVE_NUM_PTYPES 1024
 
-#define GVE_RX_BUFFER_SIZE_DQO 2048
+#define GVE_DEFAULT_RX_BUFFER_SIZE 2048
+
+#define GVE_DEFAULT_RX_BUFFER_OFFSET 2048
 
 #define GVE_XDP_ACTIONS 5
 

diff --git a/drivers/net/ethernet/google/gve/gve_ethtool.c b/drivers/net/ethernet/google/gve/gve_ethtool.c
index 233e5946905e7dfa4bb7f0bf2955cd316b352b21..e5397aa1e48f2e755f8748c94b3baed7cd2e2230 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_ethtool.c
+++ b/drivers/net/ethernet/google/gve/gve_ethtool.c
@@ -519,7 +519,7 @@ static int gve_set_tunable(struct net_device *netdev,
        case ETHTOOL_RX_COPYBREAK:
        {
                u32 max_copybreak = gve_is_gqi(priv) ?
-                       (PAGE_SIZE / 2) : priv->data_buffer_size_dqo;
+                       GVE_DEFAULT_RX_BUFFER_SIZE : priv->data_buffer_size_dqo;
 
                len = *(u32 *)value;
                if (len > max_copybreak)

diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index cc169748ffa2ca6b93d1c1362f310ab824bd2f8c..619bf63ec935b6b5222480bbc5ef139aec1823fc 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -1328,7 +1328,7 @@ static int gve_open(struct net_device *dev)
                /* Hard code this for now. This may be tuned in the future for
                 * performance.
                 */
-               priv->data_buffer_size_dqo = GVE_RX_BUFFER_SIZE_DQO;
+               priv->data_buffer_size_dqo = GVE_DEFAULT_RX_BUFFER_SIZE;
        }
        err = gve_create_rings(priv);
        if (err)
@@ -1664,7 +1664,7 @@ static int verify_xdp_configuration(struct net_device *dev)
                return -EOPNOTSUPP;
        }
 
-       if (dev->mtu > (PAGE_SIZE / 2) - sizeof(struct ethhdr) - GVE_RX_PAD) {
+       if (dev->mtu > GVE_DEFAULT_RX_BUFFER_SIZE - sizeof(struct ethhdr) - GVE_RX_PAD) {
                netdev_warn(dev, "XDP is not supported for mtu %d.\n",
                            dev->mtu);
                return -EOPNOTSUPP;

diff --git a/drivers/net/ethernet/google/gve/gve_rx.c b/drivers/net/ethernet/google/gve/gve_rx.c
index 82aa185880499f46790880968cdc61812fb4b765..7a8dc5386ffff9bd99d94eced337cf276551a88f 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_rx.c
+++ b/drivers/net/ethernet/google/gve/gve_rx.c
@@ -283,7 +283,7 @@ static int gve_rx_alloc_ring(struct gve_priv *priv, int idx)
        /* Allocating half-page buffers allows page-flipping which is faster
         * than copying or allocating new pages.
         */
-       rx->packet_buffer_size = PAGE_SIZE / 2;
+       rx->packet_buffer_size = GVE_DEFAULT_RX_BUFFER_SIZE;
        gve_rx_ctx_clear(&rx->ctx);
        gve_rx_add_to_block(priv, idx);
 
@@ -399,10 +399,10 @@ static struct sk_buff *gve_rx_add_frags(struct napi_struct *napi,
 
 static void gve_rx_flip_buff(struct gve_rx_slot_page_info *page_info, __be64 *slot_addr)
 {
-       const __be64 offset = cpu_to_be64(PAGE_SIZE / 2);
+       const __be64 offset = cpu_to_be64(GVE_DEFAULT_RX_BUFFER_OFFSET);
 
        /* "flip" to other packet buffer on this page */
-       page_info->page_offset ^= PAGE_SIZE / 2;
+       page_info->page_offset ^= GVE_DEFAULT_RX_BUFFER_OFFSET;
        *(slot_addr) ^= offset;
 }
 
@@ -507,8 +507,7 @@ static struct sk_buff *gve_rx_copy_to_pool(struct gve_rx_ring *rx,
                return NULL;
 
        gve_dec_pagecnt_bias(copy_page_info);
-       copy_page_info->page_offset += rx->packet_buffer_size;
-       copy_page_info->page_offset &= (PAGE_SIZE - 1);
+       copy_page_info->page_offset ^= GVE_DEFAULT_RX_BUFFER_OFFSET;
 
        if (copy_page_info->can_flip) {
                /* We have used both halves of this copy page, it

diff --git a/drivers/net/ethernet/google/gve/gve_tx.c b/drivers/net/ethernet/google/gve/gve_tx.c
index 9f6ffc4a54f0bb6a46c4f6daee26f429682191e1..07ba124780dfae7419af27c8b31807a8ded43fe2 100644 (file)
--- a/drivers/net/ethernet/google/gve/gve_tx.c
+++ b/drivers/net/ethernet/google/gve/gve_tx.c
@@ -819,7 +819,7 @@ int gve_xdp_xmit_one(struct gve_priv *priv, struct gve_tx_ring *tx,
        return 0;
 }
 
-#define GVE_TX_START_THRESH    PAGE_SIZE
+#define GVE_TX_START_THRESH    4096
 
 static int gve_clean_tx_done(struct gve_priv *priv, struct gve_tx_ring *tx,
                             u32 to_do, bool try_to_wake)